Remove global variable arm_linux_vfp_register_count in arm-linux-nat.c

This patch is to remove the global variable arm_linux_vfp_register_count
from arm-linux-nat.c.  This global variable is set when native gdb
looks for the right target description according HWCAP.  However,
'struct gdbarch_tdep' has already had a field have_vfp_registers, which
is a boolean about whether target has vfp registers or not.  This
patch converts this boolean field to a numeric counter to replace
global variable arm_linux_vfp_register_count.

gdb:

2015-05-28  Yao Qi  <yao.qi@linaro.org>

	* arm-linux-nat.c (arm_linux_vfp_register_count): Remove.
	(fetch_vfp_regs): Use vfp_register_count from gdbarch_tdep
	instead of arm_linux_vfp_register_count.
	(store_vfp_regs): Likewise.
	(arm_linux_fetch_inferior_registers): Likewise.
	(arm_linux_store_inferior_registers): Likewise.
	(arm_linux_read_description): Don't set
	arm_linux_vfp_register_count.
	* arm-linux-tdep.c (arm_linux_iterate_over_regset_sections):
	Adjust.
	* arm-tdep.c (arm_gdbarch_init): Add assert on
	vfp_register_count.
	* arm-tdep.h (struct gdbarch_tdep) <have_vfp_registers>: Rename
	field to vfp_register_count.  All users updated.

5 files changed, 48 insertions, 30 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index a75d3bb8d01..2c404d72b2e 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,20 @@
+2015-05-28  Yao Qi  <yao.qi@linaro.org>
+
+	* arm-linux-nat.c (arm_linux_vfp_register_count): Remove.
+	(fetch_vfp_regs): Use vfp_register_count from gdbarch_tdep
+	instead of arm_linux_vfp_register_count.
+	(store_vfp_regs): Likewise.
+	(arm_linux_fetch_inferior_registers): Likewise.
+	(arm_linux_store_inferior_registers): Likewise.
+	(arm_linux_read_description): Don't set
+	arm_linux_vfp_register_count.
+	* arm-linux-tdep.c (arm_linux_iterate_over_regset_sections):
+	Adjust.
+	* arm-tdep.c (arm_gdbarch_init): Add assert on
+	vfp_register_count.
+	* arm-tdep.h (struct gdbarch_tdep) <have_vfp_registers>: Rename
+	field to vfp_register_count.  All users updated.
+
 2015-05-28  Kyle Huey  <me@kylehuey.com>  (tiny patch)
 
 	* gdb/arm-tdep.c (arm_gdbarch_init): Perform arm_abi detection on
diff --git a/gdb/arm-linux-nat.c b/gdb/arm-linux-nat.c
index afc58178908..5c0ede60ad1 100644
--- a/gdb/arm-linux-nat.c
+++ b/gdb/arm-linux-nat.c
@@ -64,10 +64,6 @@
 /* A flag for whether the WMMX registers are available.  */
 static int arm_linux_has_wmmx_registers;
 
-/* The number of 64-bit VFP registers we have (expect this to be 0,
-   16, or 32).  */
-static int arm_linux_vfp_register_count;
-
 extern int arm_apcs_32;
 
 /* On GNU/Linux, threads are implemented as pseudo-processes, in which
@@ -460,6 +456,8 @@ fetch_vfp_regs (struct regcache *regcache)
 {
   char regbuf[VFP_REGS_SIZE];
   int ret, regno, tid;
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 
   /* Get the thread id for the ptrace call.  */
   tid = GET_THREAD_ID (inferior_ptid);
@@ -471,7 +469,7 @@ fetch_vfp_regs (struct regcache *regcache)
       return;
     }
 
-  for (regno = 0; regno < arm_linux_vfp_register_count; regno++)
+  for (regno = 0; regno < tdep->vfp_register_count; regno++)
     regcache_raw_supply (regcache, regno + ARM_D0_REGNUM,
 			 (char *) regbuf + regno * 8);
 
@@ -484,6 +482,8 @@ store_vfp_regs (const struct regcache *regcache)
 {
   char regbuf[VFP_REGS_SIZE];
   int ret, regno, tid;
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 
   /* Get the thread id for the ptrace call.  */
   tid = GET_THREAD_ID (inferior_ptid);
@@ -495,7 +495,7 @@ store_vfp_regs (const struct regcache *regcache)
       return;
     }
 
-  for (regno = 0; regno < arm_linux_vfp_register_count; regno++)
+  for (regno = 0; regno < tdep->vfp_register_count; regno++)
     regcache_raw_collect (regcache, regno + ARM_D0_REGNUM,
 			  (char *) regbuf + regno * 8);
 
@@ -519,13 +519,16 @@ static void
 arm_linux_fetch_inferior_registers (struct target_ops *ops,
 				    struct regcache *regcache, int regno)
 {
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
   if (-1 == regno)
     {
       fetch_regs (regcache);
       fetch_fpregs (regcache);
       if (arm_linux_has_wmmx_registers)
 	fetch_wmmx_regs (regcache);
-      if (arm_linux_vfp_register_count > 0)
+      if (tdep->vfp_register_count > 0)
 	fetch_vfp_regs (regcache);
     }
   else 
@@ -537,9 +540,9 @@ arm_linux_fetch_inferior_registers (struct target_ops *ops,
       else if (arm_linux_has_wmmx_registers
 	       && regno >= ARM_WR0_REGNUM && regno <= ARM_WCGR7_REGNUM)
 	fetch_wmmx_regs (regcache);
-      else if (arm_linux_vfp_register_count > 0
+      else if (tdep->vfp_register_count > 0
 	       && regno >= ARM_D0_REGNUM
-	       && regno <= ARM_D0_REGNUM + arm_linux_vfp_register_count)
+	       && regno <= ARM_D0_REGNUM + tdep->vfp_register_count)
 	fetch_vfp_regs (regcache);
     }
 }
@@ -552,13 +555,16 @@ static void
 arm_linux_store_inferior_registers (struct target_ops *ops,
 				    struct regcache *regcache, int regno)
 {
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
   if (-1 == regno)
     {
       store_regs (regcache);
       store_fpregs (regcache);
       if (arm_linux_has_wmmx_registers)
 	store_wmmx_regs (regcache);
-      if (arm_linux_vfp_register_count > 0)
+      if (tdep->vfp_register_count > 0)
 	store_vfp_regs (regcache);
     }
   else
@@ -570,9 +576,9 @@ arm_linux_store_inferior_registers (struct target_ops *ops,
       else if (arm_linux_has_wmmx_registers
 	       && regno >= ARM_WR0_REGNUM && regno <= ARM_WCGR7_REGNUM)
 	store_wmmx_regs (regcache);
-      else if (arm_linux_vfp_register_count > 0
+      else if (tdep->vfp_register_count > 0
 	       && regno >= ARM_D0_REGNUM
-	       && regno <= ARM_D0_REGNUM + arm_linux_vfp_register_count)
+	       && regno <= ARM_D0_REGNUM + tdep->vfp_register_count)
 	store_vfp_regs (regcache);
     }
 }
@@ -631,7 +637,6 @@ arm_linux_read_description (struct target_ops *ops)
 {
   CORE_ADDR arm_hwcap = 0;
   arm_linux_has_wmmx_registers = 0;
-  arm_linux_vfp_register_count = 0;
 
   if (target_auxv_search (ops, AT_HWCAP, &arm_hwcap) != 1)
     {
@@ -653,20 +658,11 @@ arm_linux_read_description (struct target_ops *ops)
       /* NEON implies VFPv3-D32 or no-VFP unit.  Say that we only support
 	 Neon with VFPv3-D32.  */
       if (arm_hwcap & HWCAP_NEON)
-	{
-	  arm_linux_vfp_register_count = 32;
-	  result = tdesc_arm_with_neon;
-	}
+	result = tdesc_arm_with_neon;
       else if ((arm_hwcap & (HWCAP_VFPv3 | HWCAP_VFPv3D16)) == HWCAP_VFPv3)
-	{
-	  arm_linux_vfp_register_count = 32;
-	  result = tdesc_arm_with_vfpv3;
-	}
+	result = tdesc_arm_with_vfpv3;
       else
-	{
-	  arm_linux_vfp_register_count = 16;
-	  result = tdesc_arm_with_vfpv2;
-	}
+	result = tdesc_arm_with_vfpv2;
 
       /* Now make sure that the kernel supports reading these
 	 registers.  Support was added in 2.6.30.  */
diff --git a/gdb/arm-linux-tdep.c b/gdb/arm-linux-tdep.c
index b6757bd1283..fd0ef5bfdd4 100644
--- a/gdb/arm-linux-tdep.c
+++ b/gdb/arm-linux-tdep.c
@@ -743,7 +743,7 @@ arm_linux_iterate_over_regset_sections (struct gdbarch *gdbarch,
 
   cb (".reg", ARM_LINUX_SIZEOF_GREGSET, &arm_linux_gregset, NULL, cb_data);
 
-  if (tdep->have_vfp_registers)
+  if (tdep->vfp_register_count > 0)
     cb (".reg-arm-vfp", ARM_LINUX_SIZEOF_VFP, &arm_linux_vfpregset,
 	"VFP floating-point", cb_data);
   else if (tdep->have_fpa_registers)
diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 750749d5fd9..4011de8c9ac 100644
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -9914,7 +9914,7 @@ arm_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   enum arm_float_model fp_model = arm_fp_model;
   struct tdesc_arch_data *tdesc_data = NULL;
   int i, is_m = 0;
-  int have_vfp_registers = 0, have_vfp_pseudos = 0, have_neon_pseudos = 0;
+  int vfp_register_count = 0, have_vfp_pseudos = 0, have_neon_pseudos = 0;
   int have_neon = 0;
   int have_fpa_registers = 1;
   const struct target_desc *tdesc = info.target_desc;
@@ -10220,7 +10220,7 @@ arm_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
 	  if (tdesc_unnumbered_register (feature, "s0") == 0)
 	    have_vfp_pseudos = 1;
 
-	  have_vfp_registers = 1;
+	  vfp_register_count = i;
 
 	  /* If we have VFP, also check for NEON.  The architecture allows
 	     NEON without VFP (integer vector operations only), but GDB
@@ -10289,7 +10289,10 @@ arm_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   tdep->fp_model = fp_model;
   tdep->is_m = is_m;
   tdep->have_fpa_registers = have_fpa_registers;
-  tdep->have_vfp_registers = have_vfp_registers;
+  gdb_assert (vfp_register_count == 0
+	      || vfp_register_count == 16
+	      || vfp_register_count == 32);
+  tdep->vfp_register_count = vfp_register_count;
   tdep->have_vfp_pseudos = have_vfp_pseudos;
   tdep->have_neon_pseudos = have_neon_pseudos;
   tdep->have_neon = have_neon;
diff --git a/gdb/arm-tdep.h b/gdb/arm-tdep.h
index bd01ec9969c..06658a00e85 100644
--- a/gdb/arm-tdep.h
+++ b/gdb/arm-tdep.h
@@ -161,7 +161,9 @@ struct gdbarch_tdep
   enum arm_float_model fp_model; /* Floating point calling conventions.  */
 
   int have_fpa_registers;	/* Does the target report the FPA registers?  */
-  int have_vfp_registers;	/* Does the target report the VFP registers?  */
+  /* The number of VFP registers reported by the target.  It is zero
+     if VFP registers are not supported.  */
+  int vfp_register_count;
   int have_vfp_pseudos;		/* Are we synthesizing the single precision
 				   VFP registers?  */
   int have_neon_pseudos;	/* Are we synthesizing the quad precision